38 -B A T E A C H I A. 



stood by the French herpetologists, which are provided with large 

 and conspicuous lumbar glands. It is upon that character, exclusively 

 to any other, that Thomas Bell reinstated the genus Pleurodema in 

 the " Zoology of the Voyage of the Beagle." 



Although it should be found that Pleurodema has a greater affinity 

 with Cystignathus than with Bombinator a fact which would bear 

 upon its systematic position yet there is no sufficient ground to com- 

 bine its species with Cystignathus in one and the same group. 



The species of this genus known to the present day are : PLEURODEMA 

 BUFONIUM, Bell ; P. DARWINII, Bell ; P. NODOSA Grd. ( Cystignathus 

 nodosus, DUM & BIBR.), and those described further on. 



1. PLEURODEMA BIBRONI, Tsch. 

 (Plate IV, figs, 33-38.) 



SPEC. CHAR. An ovoid lumbar gland on each side. Tympanum not 

 apparent. Toes margined with a membranous fold. Two meta- 

 tarsal tubercles. A cutaneous tarsal ridge. Skin generally smooth, 

 occasionally pustulous. 



SYN. Pleurodema libroni, TSCH. in M6m. Soc. Sc. nat. Neuch. II, 1838, 85. GRD. 

 Proc. Acad. Nat. Sei. Philad. VI, 1853, 420. 

 Bombinator ocellatus, Mus. Leyde. 



Cystignathus Libroni, DUM. & BIBR. Erp. gen. VIII, 1841, 410. 

 Bufo arunco, LESS. Zool. Voy. Coq. II, i, 1830, 64. PI. vu, fig. 5. 

 Pleurodema arunco, GRD. in Proc. Acad. Nat. Sci. Philad. VI, 1853, 420. 



OBSERV. In the Zoology of the " Voyage de la Coquille," Plate vn, 

 fig. 5, Lesson gives a figure of the species here referred to, under the 

 name of Bufo arunco, Schn. 



But Schneider himself is not the author of that specific name, since 

 the latter quotes Molina, " Hist, de Chile," 1, 1788, 393, who, however, 

 placed it in the genus Sana. Molina's diagnosis could never be in- 

 tended for Pleurodema bibroni, for it reads : Rana arunco, corpore 

 verrucoso, pedibus palmatis. 



Lesson's descriptions of Bufo arunco and B. thaul, are transposed 

 with regard to headings : evidently a printer's mistake. 



DESCR. The head is somewhat broader than long ; its upper sur- 

 face declivous, and the outline of the snout rounded. The nostrils 



